Mozilla proposes Do Not Track HTTP header

Emma Woollacott, 24th January 2011

Mozilla is considering introducing a 'Do Not Track' feature into Firefox, allowing users to opt out of online behavioral advertising (OBA).

The move would let users configure their browser to reject personalized advertising, with the decision being communicated to web sites and third party ad servers by sending a new Do Not Track HTTP header with every click or page view.

"We believe the header-based approach has the potential to be better for the web in the long run because it is a clearer and more universal opt-out mechanism than cookies or blacklists," says the company's head of global privacy and public policy, Alexander Fowler, in a blog post.

"The advantages to the header technique are that it is less complex and simple to locate and use, it is more persistent than cookie-based solutions, and it doesn’t rely on user’s finding and loading lists of ad networks and advertisers to work."

The problem with the new feature, as Mozilla acknowledges, is that it requires both browsers and sites to implement it to be fully effective.

"Mozilla recognizes the chicken and egg problem and we are taking the step of proposing that this feature be considered for upcoming releases of Firefox," says Fowler. "We ask that sites and advertisers join with us to recognize this new header and honor people’s privacy choices just as they are with opt-outs for OBA."

Microsoft's been promising a Do Not Track feature in Internet Explorer 9, based on blacklists. The companies are seeing the writing on the wall following a Federal Trade Commission report calling for an end to the practice.